How much would it cost to dig a new basement door to the outside?
How to install a basement door
Like any other construction question, the answer to this one depends on a number of variables, such as what your current foundation is made of, how old it is and where on the exterior of the house do you want to put the door.
Assuming it is a relatively new, like the last 20-30 years, poured concrete foundation, and that there is room to get a normal sized backhoe like a Case 580 in the yard and have room for it to back up to the work area and swing the excavated material out of the way.
You would need to hire a contractor who would dig the exterior hole and then coordinate with a concrete sawcutting company to come and cut out the opening in the basement wall into which you might want to install a passage door a little bit down the line.
You want to be sure he is also responsible for cutting the cut out concrete into smaller pieces and taking them away. There are companies all over the country which sell a set of precast stairs all set up to set against the side of the foundation and bolt them home. These serve as the bulkhead to keep dirt from collapsing back on the stairs as well as being the stairs themselves. They usually come with a set of metal bulkhead doors which can be latched from the inside and which will keep the elements out of the bulkhead area.
Depending on what part fo the country you are from you might spend between $500 to $1,500.00 for the excavation, hauling away the excess fill and setting the actual bulkhead assembly in place. Saw cutting the concrete may cost $400-$600 (very expensive tools and operators) and the bulkhead itself usually can cost around $800.00 or so.
It is much easier to have these installed when the original foundation is poured because all they do then is have the guys who place the forms leave a space blocked out for the bulkhead door, and the bulkhead itself is installed prior to backfilling so there is no particular cost associated with the installation.
If you have a block foundation you may be able to cut costs because a mason can knock out the necessary blocks and repair/build a clean sided openingin a half day or so, and if you can get the hole excavated you can also have a block bulkhead built whidh will keep your "space" open and you can then build yourself a set of wooden steps. You do have to make sure the mason know what size door you are going to install over the bulkhead, unless you decide to build them to the opening yourself from wood.